Abit is7 northbridge heatsink

my Abit mohterboard's northbridge heatsink fan is dying on my IS7. Can anyone reccommend a good cheap, quiet alternative. Preferabley under 20$. I only OC from 3.2 to 3.4ghz. So i dont need anything fancy. This fan is driving me nuts. As you see its 2:30 AM and im awoken by the absurdly loud fan . AHH back to sleep.